Uleaded blues....

[mikeb]

I have been running the car since I bought it on LRP 4 star.

Over reent months nobody seems to stock it any longer so I have been looking around to change to something a bit more plentiful.

I have looked into and been advised to go for Super Unleaded but nobody, not one garage around me stocks it.

This means that I will have to use 95 ron Unleaded or 'Premium unleaded' as my local garages call it.

Does anybody else use this in their v8 350i and what was the specification of the tuning??.

I know normally the cars are set to 8 degrees BTDC and to run unleaded the car must be tuned to 4 degrees (if the engine timing marks are correct!?).

Is this correct??, what is everybody else using petrol wise and tuning wise??.

Mike

[rev-erend]

I run mine on either LRP or super .. depending on what they have .. never needed to use unleaded.

Don't know the timing setting on my car ..

[cuneus]

Mike

Don't know where you are in S. Wales but there are Shell Optimax (98 RON) stations in Cardiff, Barry, Newport, Bridgend, Cwmbran

[mikeb]

I live in the caerphilly area.

I have tried nearly every garage in Caerphilly and the surrounding areas including: Safeway, Murco, ASDA a couple of independents etc and they have all stopped doing the LRP and most if not all of them do not do the Super unleaded either. Which leaves just ordinary 95 Ron Unleaded or diesel!.

This is beginning to nark me as I now find myself hunting around for specific garages which seem to be miles away (Cardiff).

Is there any harm in filling up with LRP and then filling up with Super unleaded (when I can find them) mix and matching the petrol in the tank on the fly, or should I just get the car tuned to run common of garden Unleaded 95 ron????.

What sort of affects will this have on the performance of the car and what tuning specs are involved???.

MikeB



>> Edited by mikeb on Monday 5th July 16:11

[petej280+2]

This might be a useful site... the history of the fuel cat is very interesting.......

www.fuelcat.co.uk/

I don't know of anyone who uses one so don't know how good they are..... Anyone got one fitted????

Pete J

[tallbloke]

I've found that normal 95RON u/l + a dose of Millers VSP is cheaper than and works better than SuperPlus or LRP. Most halfords motorworlds etc stock Millers VSP, it acts as an octane booster (you can exceed the recommended dose by 2X if you wish) and it also acts as an upper cylinder lubricant to preserve those less than superhard valve seats if you don't have heads capable of running straight unleaded. I've also found their injector cleaner to be very good...

[350matt]

The car will run fine on normal 95 unleaded, as the valve seats are already the hard type to cope, you 'may' need to retard the ignition / disconnect the vacuum advance, to prevent any pre-ignition. Other than that no other mods required

Matt

[19560]

The good news is that all of the Rover V8 engines that TVR used have hardened valve seats and will run on just about anything, you just need to adjust the timing slightly. (ie all fuel injected Rover V8s have hardened valve seats.)

The Bayford Trust 4 star at 101/102 ron is probably best but difficult to find. Shell Optimax is probably the best practicle alternative (98 ron.) The BP stuff is 97 ron. Unleaded is 95 ron. LRP is probably best avoided - not enough additive to do the job properly but enough that it may not mix very well with other fuels.

You can add millers VSP or CVL to any of the grades just adjust the timing.

I found it quite hard to adjust the timing because when you have it positioned where you want it with the strobe light when you come to tighten it up the dizzy rotates slightly - why didn't they design it so that the screw was in a different orientation?

[B19 JAE]

Ran mine on watever the garages had wen a went in usually went for the premium type but watever I put in I had no problems
I thort you could get addatives to go in the tank tho if you do have problems

[gsx600]

Run the 350 and 400 (both 1989) on what ever petrol I can get cheap> Not really notice any difference in using normal unleaded as the engines are so torkey anyway. Suppose on a track might tryu and use something a bit better than Asda special brew

[streaky]

The LRP from different fuel suppliers can be based on one of four different chemistries:
1. Potassium (K) metallic
2. Sodium (Na) metallic
3. Manganese(Mn) metallic
4. Phosphorous(P) non-metallic

In the UK there has been a general agreement to use K-based chemistry, but this is not the case on the continent, and it may be that small distributors who buy their refined petrol "on the spot" (as it were) could end up with one of the other chemistries in their tankers and thence in their supplied garages' tanks.

Streaky (who generally uses 95/97 unleaded in the 390SE, as the nearest Optimax garage is not on any of my common routes)

[jmorgan]

I have been told that LRP is to be avoided? Few reasons given among them no standard and it attacks certain fuel pipes, or rather some materials that are in thier make up?

Running on 95ron but thats tuned up by DJE for it.


Slightly off at a tangent...A while ago I was told my 350 needed leaded so was running on unleaded with an additive. It was an early one and it was the factory that supplied the info.

[seamus]

Alternatively you can search to see if there is a 4* garage near you - you'd be surprised how many there still are according to : www.leadedpetrol.co.uk/list.htm
But I would still call ahead and check first - I greedily have 3 stations within a 10 mile radius... and have only just found out..

[wedg1e]

I always use 95 RON. However in a recent (ahem) test session, top speed was somewhat below the alleged 146 mph maximum... which may of course be attributable to many things other than the potency of the fuel.

Ian

[jim meehan]

Ray Webb (helpline at tvrcc), reassured me that they had the 400 engine on dyno tests and it made no difference whatsoever to performance with optimax or 4 star or 95 ron. No additives necessary either, he said, as valve seats are indeed, as the cliche goes, bulletproof. His advice - get the basic unleaded and save a few bob and you wont feel any difference. Ask him. email [e-mail] or "refer to your local dealer"....

[rev-erend]

but if it pinks like mad on unleaded .. then for it to run OK - you will need to retard the ignition .. and I would disagree with Ray Webb that yes it's going to loose a few horses.

My own findings are that when an engine gets older - it builds up carbon deposites on valves and piston heads .. this can be helped by using higher octane fuel - which gives you more 'timing range' under which the car can run without pinking.

[mikeb]

Well, had a word with the dude who runs a near(ish) garage and he intends to keep on selling LRP.

I have done a bit of detective work and there are also other garages within reason that also sell LRP.

I have only found one garage that sells Super unleaded apart from the motorway service station type of garages, but these seem to be phasing out LRP so I have a few options.

I tried normal '95 unleaded and I definately noticed some loss of poke. It just seemed to loose a little get up and go in my opinion.

MikeB

[ferlin]

jim meehan said:

Ray Webb (helpline at tvrcc), reassured me that they had the 400 engine on dyno tests and it made no difference whatsoever to performance with optimax or 4 star or 95 ron. No additives necessary either, he said, as valve seats are indeed, as the cliche goes, bulletproof. His advice - get the basic unleaded and save a few bob and you wont feel any difference. Ask him. email [e-mail] or "refer to your local dealer"....

When I bought my 350i I rang the local dealer who did not know if it would run ok on unleaded and said that they would call me back......Im still waiting!!!
Anyway it seems to run fine without any sign of pinking

[Gerry Attrick]

There are two things to consider here. Octane rating and valve seat recession. Lead was put into petrol to help both of these. If you remove the lead, 'soft' seats will allow the valves to sink into the head. However, the V8 has hardened seats so there is no problem. This leaves the octane rating. The engine was designed, I believe, to run on 97 RON, so conventional ULG (at 95 RON) will give pinking with the same timing. If you retard the timing you should be able to stop the pinking and use ULG. The problem with retarding the timing is that the fuelling will not be optimised throughout the speed / load range (not just at WOT). This means you will lose power. You will also have poorer fuel consumption. The amount of power or fuel wastage is however, pretty small as, when these engines, were designed, they rarely ran at the lean levels we see in modern engines. I very much doubt you would be able to 'feel' any difference in the seat of the pants.

p.s. There is probably no change in exhaust note either !!!

[wedget]

I run my car on optimax with an additive and i have noticed a huge difference in poke and exhaust note, In fact when i last swapped from LRP to optimax i could feel the difference starting to happen as the optimax started to come through on a run. I dont know if my car can run on unleaded without i have tried it with 95, 97, 98 ron with and without additives and so far optimax is the best, i got no pinking from anything i tried and i only use the additive as a precation.